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Figure S8. Cytochalasin D blocks phagocytosis but has no adverse effects on production or secretion of TNF-α. (A) C57BL/6J peritoneal macrophage suspensions were pretreated with 6 μM of cytochalasin D or an equal volume of DMSO and incubated with TAMRA–S. aureus (MOI = 50) for 20 min on ice and for a further 30 min at 37°C. Phagocytosis of TAMRA–S. aureus was analyzed by flow cytometry and evaluated as the percentages of fluorescence-positive cells of the macrophage population. Data are representative of two independent experiments. (B) C57BL/6J peritoneal macrophages were pretreated with 6 μM of cytochalasin D or an equal volume of DMSO and cultured in the presence or absence of 10 ng/ml LPS, 2 µg/ml LTA, or 100 µg/ml of zymosan for 2 h. Induction of TNF-α was measured by ELISA in culture supernatants. Data are representative of three independent experiments. Error bars indicate mean ± SD of triplicates.